Clinical History

A male patient, 34 years old, complaining of right-sided tinnitus.

Imaging Findings

The right internal jugular vein (IJV) at the skull base shows a high riding bulb reaching up to a level where the internal auditory canal (IAC) can be seen. The IJV is seen protruding into the middle ear cavity with the bony boundary (sigmoid plate) thinned out.

Discussion

Background: The jugular bulb is the highest most dilated portion of the jugular vein at its junction with the sigmoid sinus. It is said to be high riding when it extends superior to the floor of the IAC. In the presence of dehiscent sigmoid plate, the jugular vein extends supero laterally from the jugular foramen into the middle ear cavity. On otoscopy, it can be seen as a bluish retro tympanic mass [1].

The true association of jugular bulb variant and tinnitus is still a matter of controversy in literature. Some believe that even if a jugular bulb variant is detected on imaging, one should search for another treatable cause [2].

Outcome: The importance of the detection of such variants lies in preventing catastrophic events in middle ear surgeries. It is therefore critically important to report such a finding to the surgeon [3].